Conventional detergents used in the vehicle care, warewashing and laundry industries include alkaline detergents. Alkaline detergents, particularly those intended for institutional and commercial use, generally contain phosphates, nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA). Phosphates, NTA and EDTA are components commonly used in detergents to sequester metal ions such as calcium, magnesium and iron.
In particular, NTA, EDTA or polyphosphates such as sodium tripolyphosphate and their salts are used in detergents because of their ability to prevent calcium, magnesium and iron from precipitating and/or solublize preexisting inorganic salts and/or soils. When calcium, magnesium and iron salts precipitate, the crystals may attach to the surface being cleaned and cause undesirable effects. For example, calcium carbonate precipitation on the surface of ware can negatively impact the aesthetic appearance of the ware, giving an unclean look. In the laundering area, if calcium carbonate precipitates and attaches onto the surface of fabric, the crystals may leave the fabric feeling hard and rough to the touch. The ability of NTA, EDTA and polyphosphates to remove metal ions facilitates the detergency of the solution by preventing hardness precipitation, assisting in soil removal and/or preventing soil redeposition into the wash solution or wash water.
While effective, phosphates and NTA are subject to government regulations due to environmental and health concerns. Although EDTA is not currently regulated, it is believed that government regulations may be implemented due to environmental persistence. There is therefore a need in the art for an alternative, and preferably environment friendly, cleaning composition that can replace the properties of phosphorous-containing compounds such as phosphates, phosphonates, phosphites, and acrylic phosphinate polymers, as well as non-biodegradable aminocarboxylates such as NTA and EDTA.